EarthLinked® Design

The use of small refrigerant tubes for heat exchange in the earth is made possible by ECR's Refrigerant Management System which consists of the Liquid Flow Control (LFC) and the Active Charge Control (ACC). Together, they achieve high efficiency direct expansion and condensation of refrigerant in the earth through Direct GeoExchange.

The ECR EarthLinked® system utilizes small tube earth loops connected in parallel. Loops can be installed in diagonal, vertical or horizontal configurations in 3" diameter bore holes, 50 to 100' in length. The system uses one to four copper DIRECT AXXESS® earth loops per ton, depending upon loop length, soil conditions and bore hole grout.

Click for description of earth loop configurations.

An important savings in installation cost of the ECR EarthLinked® system is the significant reduction in drilling cost for the small bore holes. The 3" holes for the ECR system require drilling only 11% of the volume of the 6" holes required for other GeoExchange. ECR developed the technology to economically drill small bore holes, which has been adapted for use on small drill rigs that are commercially available.

The ECR EarthLinked® system has been tested and compared against both air-source heat pumps (ASHPs) and other geothermal heat pumps (GHPs). The ECR system exceeds the efficiency of the "high efficiency" ASHPs by more than 40%, and exceeds the efficiency of a typical GHP by about 20-25%, (at an installed cost at least $1,000 -$2,000 less than the typical GHP system).

While the cost of an ECR system exceeds that of a comparably sized high-efficiency ASHP by approximately 50%, the cost payback is typically less than 40 months. Analysis of the heat pump market shows that consumers will gladly pay a premium for a high efficiency system that offers such a brief cost-recovery period and provides increased comfort and reliability.

The ECR system is also easier to install and service because no gauges or charging charts are required for determining the proper charge in the system. The ACC includes a visual indicator of the level of the liquid therein to determine the proper charge.

Water Heating Option

The EarthLinked® system also has the unique capability of water heating "on demand" during any season, or as a desuperheater in the air conditioning cycle. Click to read more about this option.

ECR EarthLinked® Advantages Over High-Efficiency ASHPs

  • Saves up to 60% in operating costs on an annual basis.
  • Increases comfort by efficiently using the renewable earth heat source to provide 100° supply air.
  • Does not lose efficiency as ambient air temperatures drop, as the ASHP does.
  • Achieves high-efficiency without having to utilize variable speed compressors or multi-speed fans.
  • Can be located in a utility room or basement because of the elimination of the need to circulate air over the exterior evaporator/condenser.
  • Quiet operation resulting from total system enclosure and elimination of exterior fan.
  • Exterior condenser/evaporator unit (fan coil in ASHP) is buried out of sight, protected from damage or theft.
  • Approximately one-half the size of a typical ASHP unit.
  • Not subject to freezing; no defrosting required.
  • Has greatly improved reliability and serviceability.
  • Eliminates the exterior condenser/evaporator coil, fan, fan motor and capacitor, defrost timer, and ancillary wiring, making it mechanically and electrically simpler.
  • Dramatically extends compressor life by reducing compressor wear by temperature fluctuations in ambient air.

ECR EarthLinked® Advantages Over Typical GHPs

  • More efficient operation of the compressor, evaporator, and condenser.
  • Eliminates large closed-loop plastic piping system, with its inefficient intermediate heat transfer. (GHP earth loops must be purchased in parts, assembled on-site, installed, filled with antifreeze and water, and pumped constantly while system is operating.)
  • Continues to operate even when evaporator surface (loop) is enveloped in ice.
  • Mechanically simpler and more reliable; easier to service.
  • Utilizes bore holes 3" in diameter in contrast to 6" bore holes.
  • Saves at least $1,000 - $2,000 in installed cost for a typical 3-ton system.
 

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